Sample preparation machine

Abstract

This invention relates to an apparatus for preparing samples. These samples will be used for making disks and solutions for subsequent analysis by chemical or physical means. The machine contains an assembly of several gas burners with a crucible above each of them for heating and melting the sample-flux mixture. Efficient mixing in the melt is obtained by providing a crucible with a new shape in combination with a periodic tilting or rotation of the crucible. Solutions are prepared by pouring the hot molten glass mixture into beakers containing an acid and by agitating the acid and the glass particles. Glass disks are prepared by placing moulds above the crucibles during heating and by turning the crucibles and the moulds upside down so that the hot molten glass mixture flows into the moulds for subsequent solidification into solid glass disks of high quality, ready for analysis without further processing. Various shapes of crucibles are disclosed. This apparatus gives a better homogeneity of the molten glass mixture within a shorter period of time.

I claim: 
     
       1. An apparatus for melting and diffusing materials comprising: a plurality of crucibles,   each said crucible being formed with at least one inner protrusion therein to form narrower passages in said crucible;   a rotatable crucible support and means for mounting said crucibles on said rotatable crucible support;   heating means for melting the content of said crucibles;   means to produce continuous deformation of the molten content of said crucible consecutive to contiuous movement of said molten content in and out of said narrower passages so as to produce substantially homogeneous diffusion of the materials in said crucibles; and   means associated with said rotatable support to pour the molten contents of diffused materials present in said crucibles, into fused material containers.   
     
     
       2. Apparatus according to claim 1, wherein said means to cause rotation of said crucibles include means for rocking said rotatable crucible support to cause continuous right and left tilting of said crucibles resulting in said continuous deformation of their molten contents. 
     
     
       3. Apparatus according to claim 2, wherein said crucibles are formed at the bottom thereof with a rounded conically shaped protrusion. 
     
     
       4. Apparatus according to claim 2, wherein said crucibles are formed at the bottom thereof with a plurality of rounded conically shaped protrusions. 
     
     
       5. Apparatus according to claim 1, wherein said crucibles are formed with at least one rounded conically shaped protrusion at the lower end of the wall thereof. 
     
     
       6. Apparatus according to claim 2 which comprises a frame, said crucible support comprising a U-shaped member mounted on said frame, said crucibles being mounted on said U-shaped member by means of U-shaped fork type holders, shaft portions associated with both legs of said U-shaped member to define the axis of rotation of said crucible support, the rocking means being coupled to said shaft portions. 
     
     
       7. Apparatus according to claim 6, wherein said crucibles are spacedly aligned along the base of said U-shaped member so that the axis of rotation of said crucible support extends through the aligned crucibles. 
     
     
       8. Apparatus according to claim 7, wherein said fused material containers consist of a plurality of moulds, said crucible support being coupled to a mould support, said mould support comprising a plurality of mould holders to hold said moulds opposite said crucibles. 
     
     
       9. Apparatus according to claim 7, wherein said fused material containers consist of a plurality of beakers adapted to contain a solution capable of dissolving said fused materials. 
     
     
       10. Apparatus according to claim 8, wherein said support is constructed to position said moulds immediately above said crucibles when fusing of said materials takes place. 
     
     
       11. Apparatus according to claim 10, wherein the pouring means comprises rotating means associated with at least one of said shaft portions to rotate said crucible support and capable of inducing an upside down rotation of said crucibles resulting in a pouring of said molten materials into said moulds. 
     
     
       12. Apparatus according to claim 9, which comprises a tilting arm formed with a toothed rack at the upper end thereof, a toothed gear meshing with said toothed rack and engaging at least one of said shaft portions, a pivot member along said tilting arm about which said tilting arm is allowed to pivot, a first engageable pin at the lower end of said tilting arm, a first pivoting latch provided with a first opening to engage said first engageable pin, the first opening of said first latch being disengageable from said first engageable pin, to permit free pivoting of said tilting arm about said pivot member and said first opening being able to engage said first engageable pin and to block the pivoting of said tilting arm, means to cause oscillation of said tilting arm about said pivot member when said first latch is disengaged from said first engageable pin so as to induce a back and forth rotation of said tooth gear which provides said right and left tilting of said crucibles, and means to cause said toothed gear to ride along said toothed rack when said tilting arm is blocked resulting from engagement of said first latch with said first engageable pin so as to cause said crucibles to rotate substantially upside down to pour their contents into said moulds. 
     
     
       13. Apparatus according to claim 12, which comprises an overturning arm pivoted along its length on said pivot member, the upper end of said overturning arm being connected to said toothed gear for free rotation thereof, a second engageable pin at the lower end of said overturning arm, a second opening of said first pivoting latch to engage said second engageable pin, so that when said second opening of said first second latch is disengaged from said second engageable pin, to permit free pivoting of said overturning arm about said pivot member, and when said second opening is engaged with said second engageable pin, to block the pivoting of said overturning arm, so that when said tilting arm is blocked by said first latch, said overturning arm is allowd to pivot, means to cause oscillation of said overturning arm about said pivot member when said second latch is disengaged from said first second engageable pin and said tilting arm is blocked by said first latch to cause said toothed gear to ride back and forth on said toothed rack thereby provoking a sufficient rotation of said crucible support to overturn said crucibles and to pour their contents into said moulds. 
     
     
       14. Apparatus according to claim 13, which comprises means for injecting oxygen at the base of the burners to increase temperature of flame. 
     
     
       15. Apparatus according to claim 13, which comprises means for introducing a releasing agent into said crucibles during fusion. 
     
     
       16. Apparatus according to claim 15, wherein said means for introducing said releasing agent comprise a cup for each crucible adapted to contain said releasing agent in the form of pellets, solenoids to push said pellets out of said cups into said crucibles, and means operable to activate said solenoids. 
     
     
       17. Apparatus according to claim 13, wherein said support for holding said moulds is pivoted at the rear portion thereof to the rear of said U-shaped member, a second latch is provided to position the mould holding support and the U-shaped member relative to one another at angles of 0° and about 30° with the moulds substantially facing said crucibles. 
     
     
       18. Apparatus according to claim 17, which comprises a plurality of beakers adapted to contain a solution capable of dissolving said fused materials, so that when it is intended to dissolve said fused materials in said solution, said moulds are removed from said mould holding support and when overturning said crucible said fused materials are poured directly into said beakers. 
     
     
       19. Apparatus according to claim 18 which comprises means for mixing the content of said solution in said beakers. 
     
     
       20. Apparatus according to claim 5, wherein said means to produce continuous deformation of said molten content of said crucibles comprises means to set said crucibles at an angle with respect to the vertical, and means to induce rotation of said crucible while at said angle. 
     
     
       21. Apparatus according to claim 1, wherein the heating means comprise gas burners placed underneath each said crucible. 
     
     
       22. Apparatus according to claim 1, wherein the heating means comprise electrical heating means. 
     
     
       23. Apparatus according to claim 1, which comprises duct means connected to a supply of air or oxygen, and leading to each of said crucibles, and means to introduce air or oxygen into said crucibles during fusion. 
     
     
       24. A crucible for fusing materials which is formed with substantially cylindrical walls and a substantially flat bottom, characterized in that it comprises at least one inner protrusion to form narrow passages in said crucible; and means for reciprocably tilting said crucible.   
     
     
       25. A crucible according to claim 24, where said protrusion is formed at the bottom thereof and is a rounded conically shaped protrusion. 
     
     
       26. A crucible according to claim 25, which comprises a plurality of said rounded conically shaped protrusions at the bottom thereof. 
     
     
       27. A crucible according to claim 26, wherein said plurality of rounded conically shaped protrusions are disposed in a row at the bottom of said crucible. 
     
     
       28. A crucible according to claim 25, wherein said rounded conically shaped protrusion is formed at the lower end of the wall of said crucible. 
     
     
       29. A method for melting and diffusing materials by heating said materials in a crucible until fusion, and stirring the resulting molten mixture, the improvement which comprises providing said crucible with at least one inner protrusion therein to form narrower passages in said crucible, and producing a continuous deformation of the molten content of said crucible consecutive to continuous movement of said molten content in and out of said narrower passages so as to produce substantially homogeneous diffusion of said materials in said crucible. 
     
     
       30. A method according to claim 29, wherein said continuous deformation is produced by rocking the crucible to cause continuous right and left tilting thereof until said diffusion is obtained. 
     
     
       31. Apparatus for diffusing materials comprising: a crucible having substantially cylindrical walls, a substantially flat bottom, and an inner protrusion means for forming a narrow passage in said crucible; and   means for moving material contained within said crucible in and out of said narrow passage and for reciprocably tilting said crucible.   
     
     
       32. An apparatus according to claim 31, wherein said protrusion is formed at the bottom of said crucible and is a rounded conically shaped protrusion. 
     
     
       33. A crucible for fusing materials which is formed with substantially cylindrical walls and a substantially flat bottom, comprising at least one inner protrusion to form narrow passages in said crucible; and means for rotating said crucible about an inclined axis.